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GB522000A - Improvements in or relating to carrier current signalling systems - Google Patents

Improvements in or relating to carrier current signalling systems

Info

Publication number
GB522000A
GB522000A GB3164238A GB3164238A GB522000A GB 522000 A GB522000 A GB 522000A GB 3164238 A GB3164238 A GB 3164238A GB 3164238 A GB3164238 A GB 3164238A GB 522000 A GB522000 A GB 522000A
Authority
GB
United Kingdom
Prior art keywords
carrier
modulating
relating
arrangement
current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB3164238A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JOHN ERNEST THOMAS PARKER
Automatic Telephone and Electric Co Ltd
Original Assignee
JOHN ERNEST THOMAS PARKER
Automatic Telephone and Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by JOHN ERNEST THOMAS PARKER, Automatic Telephone and Electric Co Ltd filed Critical JOHN ERNEST THOMAS PARKER
Priority to GB3164238A priority Critical patent/GB522000A/en
Publication of GB522000A publication Critical patent/GB522000A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03C—MODULATION
    • H03C1/00—Amplitude modulation
    • H03C1/52—Modulators in which carrier or one sideband is wholly or partially suppressed
    • H03C1/54—Balanced modulators, e.g. bridge type, ring type or double balanced type
    • H03C1/56—Balanced modulators, e.g. bridge type, ring type or double balanced type comprising variable two-pole elements only

Landscapes

  • Selective Calling Equipment (AREA)

Abstract

522,000. Modulating systems. AUTOMATIC TELEPHONE & ELECTRIC CO., Ltd., PARKER, J. E. T., and McCUSKER, J. B. Nov. 1, 1938, No. 31642. [Class 40 (v)] In a carrier current system modulation and demodulation is effected by cold discharge tubes. The arrangement shown in Fig. 1 suppresses both the carrier and the modulating circuit. Audio current is fed at A and carrier at C, the side-bands being obtained at M. The cold discharge tubes N are biassed just short of ignition by a D.C. source connected to the terminals +, -. In a modified arrangement the lower half of Fig. 1 is omitted thus only suppressing the carrier and not the modulating current. This arrangement is further modified by replacing the two tubes by a single tube with three electrodes. Demodulation is effected by feeding the received signal at A or M and a local carrier at A.
GB3164238A 1938-11-01 1938-11-01 Improvements in or relating to carrier current signalling systems Expired GB522000A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB3164238A GB522000A (en) 1938-11-01 1938-11-01 Improvements in or relating to carrier current signalling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3164238A GB522000A (en) 1938-11-01 1938-11-01 Improvements in or relating to carrier current signalling systems

Publications (1)

Publication Number Publication Date
GB522000A true GB522000A (en) 1940-06-06

Family

ID=10326218

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3164238A Expired GB522000A (en) 1938-11-01 1938-11-01 Improvements in or relating to carrier current signalling systems

Country Status (1)

Country Link
GB (1) GB522000A (en)

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